[media] media/.../soc-camera: convert drivers to use the new vb2_queue dev field

Stop using alloc_ctx and just fill in the device pointer.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>